抄録
A cylindrical wave is effective for the inspection of a long pipe, because its attenuation coefficient is very small. We made an electromagnetic acoustic tranceducer (EMAT) for the cylindrical wave of a pipe. As the first step, we aimed at evaluating the optimum specification of the EMAT and the fundamental feature of cylindrical wave using a steel pipe of 43mm diameter and 2mm thickness. The single and multi-channel type EMATs were produced by way of trial and tested. The basic characteristics of a cylindrical wave were investigated using the optimum EMAT.
